Chainstay protector with spaced protrusions

ABSTRACT

A bicycle includes a chainstay protector having an upper surface including a valley, a first peak, and a second peak. The first peak extends upwardly from the valley toward the chain and has a first contact surface positioned to contact the chain a first height above the valley. The second peak extends upwardly from the valley toward the chain and has a second contact surface positioned to contact the chain a second height above the valley. The first contact surface is spaced from the second contact surface by a gap that is at least 5 times the first height. Each of the first and second contact surfaces has a length that is less than the length of the gap and less than two times a pitch of the chain.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. Application No. 17/464,944,filed Sep. 2, 2021, which is a continuation of U.S. Application No.16/381,220, filed Apr. 11, 2019, now US Patent No.11,110,987, whichclaims the benefit under 35 U.S.C. § 119(e) of U.S. ProvisionalApplication No. 62/657,467, filed Apr. 13, 2018, the entire contents ofeach of which are incorporated herein by reference.

BACKGROUND

The present invention relates to bicycle chainstay protectors.

Riding a bicycle over an uneven terrain often causes the chain of thebicycle to oscillate vertically from its static position. In somesituations, the upper leg of the chain will contact the chainstay.

In order to inhibit damage to the chainstay caused by contact with thechain, and vice versa, bicycles commonly include chainstay protectors.Chainstay protectors typically comprise a metallic or plastic layer thatis secured (e.g., clamped, fastened or adhered) to the chainstay in thearea immediately above or below the chain.

As the bicycle is ridden over uneven terrain, the chain will movevertically and contact the chainstay protector, usually resulting in aloud slapping sound. This slapping sound can be undesirable, so it wouldbe beneficial if the volume of that sound could be reduced.

SUMMARY

The present invention provides a bicycle comprising front and rearwheels, a chain adapted to transfer power to the rear wheel, and a framesupported by the front and rear wheels. The frame includes a chainstayprotector having an upper surface positioned below the chain. The uppersurface includes a valley, a first peak, and a second peak. Third andfourth peaks also can be provided, but the total number of peaks can beless than eight. The first peak extends upwardly from the valley towardthe chain and has a first contact surface positioned to contact thechain a first height above the valley. The second peak extends upwardlyfrom the valley toward the chain and has a second contact surfacepositioned to contact the chain a second height above the valley. Thefirst contact surface can be spaced from the second contact surface by agap that is at least 5 times the first height, and can be greater thanor equal to approximately 8 times and less than or equal toapproximately 20 times the first height or greater than or equal toapproximately 10 times and less than or equal to approximately 12 timesthe first height. Each of the first and second contact surfaces can havea length that is less than the length of the gap and less than two timesa pitch of the chain.

In one embodiment, the chainstay protector is mounted on a chainstaymember of the frame, and the chainstay protector comprises a baseportion comprising a first material, and an upper portion secured to thebase portion and defining part of the upper surface. The upper portioncomprises a second material that is more resilient than the firstmaterial. The base portion includes a first opening aligned with thefirst peak, and a first pad of second material extends through the firstopening and contacts the chainstay member. The base portion also caninclude a second opening aligned between the first and second peaks, anda second pad of second material extends through the second opening andcontacts the chainstay member.

In another embodiment, the chainstay protector comprises a nose portionon a front end of the chainstay protector. The nose portion is made ofthe resilient second material and does not include the first material ofthe base portion. The nose portion has a nose length that is at leastapproximately 5% or at least approximately 10%, of the overall length ofthe chainstay protector.

In another embodiment, a bicycle includes front and rear wheels, a chainadapted to transfer power to the rear wheel, the chain having a pitch,and a frame supported by the front and rear wheels, the frame includinga chainstay protector having an upper surface positioned below thechain. The upper surface includes a valley, a first peak extendingupwardly from the valley toward the chain and having a first contactsurface positioned to contact the chain a first height above the valley,and a second peak extending upwardly from the valley toward the chainand having a second contact surface positioned to contact the chain asecond height above the valley. The first contact surface is spaced fromthe second contact surface by a gap that is at least 5 times the firstheight.

In another embodiment, a chainstay protector is adapted to be mounted ona chainstay member of a bicycle and to be contacted by a chain of thebicycle. The chainstay protector includes an upper surface adapted to bepositioned below the chain. The upper surface includes a valley, a firstpeak extending upwardly from the valley toward the chain and having afirst contact surface positioned to contact the chain a first heightabove the valley, and a second peak extending upwardly from the valleytoward the chain and having a second contact surface positioned tocontact the chain a second height above the valley. The first contactsurface is spaced from the second contact surface by a gap that is atleast 5 times the first height.

Other aspects of the invention will become apparent by consideration ofthe detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of a bicycle having a chainstay assembly embodyingthe present invention.

FIG. 2 is a perspective view of the chainstay assembly of FIG. 1 .

FIG. 3 is an exploded view of the chainstay assembly of FIG. 2 includinga chainstay member and a chainstay protector.

FIG. 4 is an upper rear perspective view of the chainstay protector ofFIG. 3 .

FIG. 5 is an upper front perspective view of the chainstay protector ofFIG. 3 .

FIG. 6 is a lower rear perspective view of the chainstay protector ofFIG. 3 .

FIG. 7 is a section view taken along line 7-7 in FIG. 2 .

FIG. 8 is a section view taken along line 8-8 in FIG. 2 .

FIG. 9 is a section view taken along line 9-9 in FIG. 4 .

FIG. 10 is side view of the chainstay assembly being contacted by achain.

DETAILED DESCRIPTION

Before any embodiments of the invention are explained in detail, it isto be understood that the invention is not limited in its application tothe details of construction and the arrangement of components set forthin the following description or illustrated in the following drawings.The invention is capable of other embodiments and of being practiced orof being carried out in various ways.

FIG. 1 illustrates a bicycle 20 including a frame 22, a saddle 24 forsupporting the rider, handlebars 26 for steering the bicycle 20, a crankassembly 28 for pedaling the bicycle 20, and front and rear wheels 30,32supporting the frame 22. A chain 34 connects the crank assembly 28 tothe rear wheel 32 to transfer power to the rear wheel 32.

The frame 22 is supported by the front and rear wheels 30,32 andincludes a chainstay member 36 connected between the portion of theframe 22 supporting the crank assembly 28 and a rear wheel support 38. Achainstay protector 40 is secured (e.g., removably secured) to thechainstay member 36 to protect the chainstay member 36 from damage fromimpact by the chain 34, and vice versa, and to reduce the noiseassociated with such impact.

Although bicycle 20 is illustrated as a human-powered bicycle withoutmotorized assistance, in other embodiments, bicycle 20 can beimplemented as a motor-assisted bicycle, such as, for example, anelectric bicycle (e.g., a pedal-assist electric bicycle).

Referring to FIG. 2 , the chainstay protector 40 defines an uppersurface below the chain 34 and adapted to be contacted by the chain 34.The upper surface includes a plurality of protrusions formed by hollowpeaks (two central peaks 42 and two end peaks 44) extending upwardlyfrom intermediate valleys 46. Referring to FIG. 3 , each peak 42,44 hasa contact surface 48 (i.e., the uppermost, flat surface of the peaks)positioned to contact the chain 34. In the illustrated embodiment, thecontact surfaces 48 have a length L1 of approximately 12 millimeters. Awidth W1 of the contact surfaces 48 is approximately 16 millimeters forthe front three peaks and about 10 millimeters for the rear peak 44. Inother embodiments, different values and/or ranges can be implemented forthe lengths L1 and/or widths W1 of contact surfaces 48. In furtherembodiments, two or more of lengths L1 of contact surfaces 48 and/or twoor more of widths W1 of contact surfaces 48 can be different from eachother or the same as each other.

Referring to FIG. 7 , the peaks 42,44 each have a height H of about 5millimeters and are spaced from adjacent peaks by a gap G (FIG. 3 ) ofapproximately 55 millimeters. In some embodiments, no other portion ofthe chainstay protector 40 is positioned directly between the contactsurfaces 48 of adjacent peaks 42, 44. In other embodiments, differentvalues and/or ranges can be implemented for the heights H of the peaks42,44, and/or gaps G between peaks 42,44. In further embodiments, two ormore of the heights H of the peaks 42,44 and/or two or more of the gapsG between peaks 42,44 can be different from each other or the same aseach other.

It has been found that the precise dimensions of the chainstay protector40 and the peaks can vary depending on the length of the chainstaymember 36 being protected. For example, as a length of the chainstaymember 36 increases, a larger number of peaks may be implemented toachieve a desirable result. It has further been found that the gap Gbetween adjacent peaks can vary depending on the height H of the peaks.As the height H is increased, the gap G may be increased. For example,the ratio of the gap G to the height H can be greater than or equal toapproximately 5:1 and less than or equal to approximately 20:1, and infurther examples, greater than or equal to approximately 8:1 and lessthan or equal to approximately 15:1. In the illustrated embodiment, theratio is approximately 11:1. In further embodiments, the ratio of thegap G to the height H can be greater than or equal to approximately 5:1,8:1, or 10:1. In these or other embodiments, the ratio of the gap G tothe height H can be less than 12:1, 15:1, or 20:1.

It has also been found that the length L1 of the contact surfaces 48 canbe positioned below a link length of the chain 34 in order toeffectively dissipate the kinetic energy of the chain 34. For example,with a standard bicycle chain implemented for chain 34 having a linklength of approximately 25.4 millimeters (corresponding to a pitch P(FIG. 10 ) between rollers of chain 34 of approximately 12.7millimeters), the illustrated embodiment has a contact surface 48 with alength L1 of approximately 12 millimeters. For example, in these orother embodiments, the length L1 of the contact surface 48 can be lessthan or equal to approximately one or two times the pitch P of chain 34.

The width W1 of the contact surfaces 48 also can vary and can beprimarily based on the width of the chainstay member 36 being protected.For example, in the illustrated embodiment, the chainstay member 36 hasa width W2 (FIG. 7 ) of approximately 20 millimeters and the width W1 ofeach of the front three contact surfaces 48 is approximately 16 mm, orapproximately 80% of the width W2 of the chainstay member 36. Therearmost peak 44 can have a contact surface with a width W2 that issubstantially less due to the reduced exposure of that portion of thechainstay member 36 to contact with the chain 34. Other embodiments caninclude different values and ranges of values for the widths W1, W2, aswell as different ratios of the widths W1, W2 than that illustrated.

Referring to FIGS. 4-8 , the illustrated chainstay protector 40 is madefrom a base portion 50 and an upper portion 52 co-molded to the baseportion 50. The base portion 50 comprises a first material. For example,the first material can comprise a glass-filled polymer, such as nylon orpolypropylene, that provides stiffness to the chainstay protector 40.Further, the upper portion 52 comprises a second material. The secondmaterial can be different than the first material. For example, thesecond material can comprise a thermoplastic rubber or polymer thatprovides a more resilient surface for contact by the chain 34. In theillustrated embodiment, the upper portion 52 defines substantially theentire (e.g., most or a majority of) upper surface to be contacted bythe chain 34, thereby providing a more resilient and quieter impact withthe chain 34. In other embodiments the base portion 50 is attached tothe upper portion 52 other than through co-molding (e.g., via afastener, snap fit-arrangement, etc.). As illustrated in FIGS. 7 and 8 ,in some embodiments, a portion of the base portion 50 at least partiallywraps around or otherwise extends alongside and below a portion of thechainstay member 36, while the upper portion 52 remains generally abovethe chainstay member 36.

In order to further quiet the chain impact, in the illustratedembodiment the base portion 50 includes multiple openings 56, 58 (FIGS.7 and 8 ) through which the second material of the upper portion 52 ispositioned to contact the chainstay member 36. More specifically,referring to FIGS. 7-9 , the base portion 50 includes first openings 56aligned with the two central peaks 42 and second openings 58 alignedwith the three valleys 46 between the four peaks 42, 44. The firstopenings 56 are relatively large and provide a path for the resilientsecond material to pass through the base portion 50 to create first pads60 (FIG. 8 ) under the central peaks 42. These first pads 60 each caninclude a bottom surface 62 (FIG. 9 ) that extends beyond the innersurface 64 of the base portion 50 to create an interference fit with thechainstay member 36 so that contact between the chainstay protector 40and the chainstay member 36 is provided primarily by the resilientsecond material to thereby absorb impact from the chain 34 and inhibitthe amount of noise from the impact. In other embodiments, openings 56and/or openings 58 can be omitted.

The second openings 58 can be smaller than the first openings 56 andprovide a path for the resilient second material to pass through thebase portion 50 to create second pads 66 (FIG. 7 ) under the threevalleys 46 between the peaks 42,44. These second pads 66 each caninclude a bottom surface 68 (FIG. 9 ) that extends beyond the innersurface 64 of the base portion 50 to create an interference fit with thechainstay member 36 so that contact between the chainstay protector 40and the chainstay member 36 is provided primarily by the resilientsecond material to thereby absorb impact from the chain 34 and inhibitthe amount of noise from the impact.

As illustrated in FIG. 9 , in the illustrated embodiment the chainstayprotector 40 has an overall length L2 of about 305 millimeters, andcomprises a nose portion 70 with a length L3 of about 35 millimeters ona front end of the chainstay protector 40. Other embodiments includevarious other values and ranges for the lengths L2, L3. The base portion50 of the chainstay protector 40 can stop short of and not extend to thenose portion 70, and therefore the nose portion 70 can be made of theresilient second material and not the stiffer first material of the baseportion 50. This provides a nose portion 70 that is very resilient andcan resiliently conform to variations in the shape of the chainstaymember 36. For example, if the chainstay member 36 has a weld beadacross its surface being covered by the chainstay protector 40, theresilient nose portion 70 can flex to conform to the weld bead toprovide a functional and aesthetically pleasing interface between thechainstay protector 40 and the chainstay member 36. In some embodiments,the nose portion 70 has a nose length L3 that is at least approximately5% of the overall length L2. In other embodiments, length L3 can be atleast approximately 10% of the overall length L2.

The illustrated chainstay protector 40 is resilient and is designed withan interference fit with the chainstay member 36 to facilitate resilientengagement with the chainstay member 36. In addition, referring to FIG.3 , the chainstay protector 40 is fastened to the frame at a pivot pointon the frame, in this case a Horst pivot 72 between the chainstay member36 and a rear wheel support 38 (FIG. 1 ). Specifically, and asillustrated in FIG. 3 , the Horst pivot 72 is provided by a pivot bolt74, and the chainstay protector 40 is fastened to the pivot bolt 74 by aprotector bolt (not shown) threaded into the pivot bolt 74.

In operation, and referring to FIG. 10 , when the chain 34 deflectsdownward, the chain 34 will first contact one or more of the peaks42,44. After this initial contact, the kinetic energy of the chain 34will be slowly dissipated as the chain 34 pivots around the peaks 42,44,thereby substantially reducing the downward speed of the chain 34gradually rather than suddenly. The result is a less severe impactbetween the chain 34 and the chainstay protector 40, which reduces theamount of noise generated by the impact. In many embodiments, the heightand spacing of the peaks 42,44 can be configured to prevent orsubstantially limit contact between the chain 34 and the valleys 46 ofthe chainstay protector 40.

While the chainstay protector 40 has been described and illustrated asextending over and/or contacting the chainstay member 36, in otherembodiments the chainstay protector 40 may extend over and/or contactother components (e.g., frame members) of the bicycle 20. For example,the bicycle 20 may include a frame member that extends below or above atleast a portion of the chain 34, and may be susceptible to beingcontacted by the chain 34. The chainstay protector 40 may therefore becoupled to such a frame member, for example in the same manner asdescribed above with respect to the chainstay member 36, so that thechain 34 does not contact the frame member, and so that a volume levelis reduced.

Various features and advantages of the invention are set forth in thefollowing claims.

1. A bicycle comprising: a front wheel and a rear wheel spaced from thefront wheel, wherein the rear wheel is configured to rotate about anaxis; a chain adapted to transfer power to the rear wheel, the chainhaving a pitch; and a frame supported by the front wheel and the rearwheel, the frame including a chainstay protector having an upper surfacepositioned below the chain, the upper surface including: a valley; afirst peak extending upwardly from the valley toward the chain andhaving a first surface positioned to contact the chain a first heightabove the valley; and a second peak extending upwardly from the valleytoward the chain and having a second surface positioned to contact thechain a second height above the valley, the first surface being spacedfrom the second surface by a gap, wherein the gap has a length thatextends along a plane that is perpendicular to the axis, wherein thelength of the gap is at least one of: at least 5 times the first height,or at least two times the pitch of the chain.
 2. The bicycle as claimedin claim 1, wherein the length of the gap is at least 5 times the firstheight, and wherein the length of the gap is greater than or equal to 8times the first height and less than or equal to 20 times the firstheight.
 3. A bicycle as claimed in claim 2, wherein the length of thegap is at least 5 times the first height, and wherein the length of thegap is greater than or equal to 10 times the first height and less thanor equal to 12 times the first height.
 4. The bicycle of claim 1,wherein the length of the gap is at least two times the pitch of thechain, and wherein the length of the gap is at least three times thepitch of the chain.
 5. A bicycle as claimed in claim 4, wherein thelength of the gap is at least two times the pitch of the chain, andwherein the length of the gap is at least four times the pitch of thechain.
 6. A bicycle as claimed in claim 5, wherein the length of the gapis less than five times the pitch of the chain.
 7. The bicycle of claim1, wherein the first surface is a first, uppermost, flat contact surfaceof the first peak.
 8. The bicycle of claim 7, wherein the second surfaceis a second, uppermost, flat contact surface of the second peak.
 9. Thebicycle of claim 1, wherein the first surface has a first width, and thesecond surface has a second width, wherein the first width and thesecond width are each measured along a direction perpendicular to theplane, and wherein the first width is different than the second width.10. The bicycle as claimed in claim 1, wherein there is no other portionof the upper surface directly between the first surface and the secondsurface.
 11. The bicycle as claimed in claim 1, wherein the chainstayprotector further comprises: a third peak extending upwardly from thevalley toward the chain and having a third surface positioned to contactthe chain a third height above the valley; and a fourth peak extendingupwardly from the valley toward the chain and having a fourth surfacepositioned to contact the chain a fourth height above the valley. 12.The bicycle as claimed in claim 1, wherein the chainstay protector ismounted on a chainstay member of the frame, and wherein the chainstayprotector comprises: a base portion comprising a first material; and anupper portion secured to the base portion and defining part of the uppersurface, the upper portion comprising a second material that is moreresilient than the first material, wherein the base portion comprises afirst opening aligned with the first peak, and wherein a first pad ofthe second material extends through the first opening and contacts thechainstay member.
 13. The bicycle as claimed in claim 1, wherein thelength of the gap is least 5 times the first height, and is also atleast two times the pitch of the chain, and wherein the length of thegap is greater than or equal to 8 times the first height and less thanor equal to 20 times the first height.
 14. The bicycle as claimed inclaim 1, wherein the first height is different than the second height.15. The bicycle as claimed in claim 1, wherein the chainstay protectorfurther comprises: a third peak extending upwardly from the valleytoward the chain and having a third surface positioned to contact thechain a third height above the valley, wherein the gap is a first gap,wherein the second surface is spaced from the third surface by a secondgap.
 16. The bicycle as claimed in claim 15, wherein the length of thefirst gap is different than a length of the second gap.
 17. A chainstayprotector adapted to be mounted on a chainstay member of a bicycle andto be contacted by a chain of the bicycle, the chainstay protectorcomprising an upper surface adapted to be positioned below the chain,the upper surface including: a valley; a first peak extending upwardlyfrom the valley toward the chain and having a first surface positionedto contact the chain a first height above the valley; and a second peakextending upwardly from the valley toward the chain and having a secondsurface positioned to contact the chain a second height above thevalley, the first surface being spaced from the second surface by a gap,wherein the gap has a length that extends along a plane that isconfigured to be perpendicular to a rotational axis of a rear wheel ofthe bicycle, wherein the a length of the gap is at least one of: atleast 5 times the first height, or is configured to be at least twotimes the pitch of the chain.
 18. The chainstay protector of claim 17,wherein the first surface is a first, uppermost, flat contact surface ofthe first peak.
 19. The chainstay protector of claim 18, wherein thesecond surface is a second, uppermost, flat contact surface of thesecond peak.
 20. The chainstay protector of claim 17, wherein the firstheight is different than the second height.